The key element behind ice rink design is the effectiveness of the refrigerant system that is used to maintain the ice surface during the arena’s operation.

Most ice pad surfaces are formed and maintained by pumping calcium chloride brine solution or glycol through 6" – 8" (150 mm – 200 mm) diameter feed and return metal pipes.

The solution is processed through a chiller, which in turn, feeds 1.25" (32 mm) diameter pipes that run perpendicular to the feeder pipes and under the ice pad to actually produce the ice surface (see Figure 1). The larger feed and return pipes are usually hung on metal angle brackets inside a 2.5' wide x 2.5' deep (750 mm x 750 mm) concrete header trench. The 2" (50 mm) treated lumber covers the top of the header trench, so it can be removed for servicing.

Under normal conditions, where these pipes are left uninsulated, 3" – 5" (75 mm – 125 mm) of solid ice can build up during operation. The refrigerant system sustains an extra load to maintain the buildup, thus consuming more electrical energy. The number of extra Btu/hr (watts) of energy can vary from one arena to another, and detailed calculations are required to obtain this number.

In calculating actual energy efficiency, several factors should be considered:

• Feed/return pipes
  • k-factor (thermal conductivity) of material
  • wall thickness
  • outside diameter
  • length
• Process temperature in/out
• Ambient temperature: seasonal or full-year operation
• Relative humidity of environment

For assistance in calculating potential energy savings that can be achieved by incorporating STYROFOAMâ„¢ Brand Extruded Polystyrene Insulation in ice arena refrigerant lines, please contact us.

For product recommendations and technical assistance, contact us when you’re ready to dig in to your next geotechnical project.